package com.lyt.springboot.util.algorithm;

public class ReverseList {
     public  static class ListNode{
         int val;
         ListNode next;
         public ListNode(int val,ListNode next) {
             this.val= val;
             this.next = next;
         }

    }
    public static ListNode iterate(ListNode head) {
         ListNode pre = null;
         ListNode temp ;
         ListNode cur = head;
         while(cur !=null) {
             temp = cur.next;
             //变动后
             cur.next=pre;
             pre = cur;
             cur= temp;
         }
         return pre;
    }

    public static void main(String[] args) {
        ListNode node5 = new ListNode(5,null);
        ListNode node4 = new ListNode(4,node5);
        ListNode node3 = new ListNode(3,node4);
        ListNode node2 = new ListNode(2,node3);
        ListNode node1 = new ListNode(1,node2);
        ListNode iterate = iterate(node1);
        System.out.println(iterate);
    }
}
